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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #42 ·
Here's my car to his point. Must be corrosion in the wiring somewhere, idk.
https://youtu.be/HUPtta9adww



This is accurate too.

Great thread. Love how good your posts are!

Edits: Other Notes

TPS will not be 0 -100. I think mine is 12% - 97%... so don't be worried about that.

Max safe temp for coolant is keeping it below boiling, but more importantly, letting the engine come down in temperature evenly so you don't warp the heads. Iron and Aluminum cool at different rates. Coolant at 15psi (radiator cap) doesn't boil till 250+ so keep it below that. Here's a link to show some more info: https://durathermfluids.com/pdf/techpapers/pressure-boiling-point.pdf

Lastly, I can't make heads or tails as to why the two pins are listed differently... but according to our bible (if you don't know about Stealth316, you should check it out... everything in there!) the ECU pinouts for 91-97 all say pin 52, while 99's say pin 62 is for IAT.

Stealth 316 - ECM pin assignments

Hope some of that helps
Appreciate the info. and video link. Yeah I'm not too worried about the coolant temp, it was just something I noticed was pretty high in my logs. The dash gage seems to be reading proportionally to what I'm seeing there. Glad to know my TPS range is making sense too –one less thing for me to check.
I fixed my post above about the ECM pin numbers –I was looking at the wrong section when comparing it to the test in Vol I.




Great intro. Check all your tail light sockets for ground. I had similar problems with my 97 SL when I first got it. Turn the lights on with CC engaged would disable it, inside lights would flicker. Took it to a family run Auto-electric shop, the dad ran it down in 10 minutes. The ground wire is embedded in the base of the socket. He played around with it trying to take it out but no dice. Some how he got it to ground so it's OK for now. We put dielectric grease on it after cleaning up the crud. Works great for now but I need to look at replacing it. Had about the same problem with my 97 VR4, cleaned up the sockets, put Dielectric grease, no more problem. Hope this helps.

Thanks for this too leadfoot. I’m all ears as to where to check for possible bad grounds, so I’ll check those areas out when I get back to it.
 

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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #43 ·
I was getting sick of crawling under the steering wheel to pin out my MAF back to the ECM, so I decided to do some work on the boost leak checker.

Here's a shot of what I made up:


I fashioned a shutoff valve and a regulator to a whip line so that I can quick disconnect between my checker for the GT (the one with the 2" line meeting at the tee fitting) and the one for my F250 pickup (the 3" one with the gage on it). A combination of Lowe's and Harbor Freight parts make this all pretty cheap to put together.

Here it is installed:


Here's a video of the first test on the GT:
https://youtu.be/_z67S10WYvI

So lots of leaks. Three right on the top near the throttle body, 1) the green vacuum line, 2) Base Idle Set Screw, and 3) the flange for the Idle Stepper Controller. I’ll fix those, then see if I can get it to hold any pressure.
 

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correct me if im wrong, but some pressure should bleed off during a boost test, even when all leaks are secured, some air will get past your rings and valves when the engine is stopped, but the bleeding off should be slow, if i charge my intake to 15 psi, I lose pressure slowly, about 1 psi ever 2-3 seconds.
 

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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #45 ·
I fixed the easy ones, now the hard ones are apparent. My front three injectors are bubbling a lot, so I'm sure the rears are just as bad. Which stinks because the intake manifold flange appears to be sealed perfectly.

I'm sure injectors are original, so I'll have to start looking at replacements (there goes another $520).

My BOV is leaking real bad as well. I can't pressurize above 10psi without it popping. I tested it with a hand pump, it's not supposed to move until 16inHg, mine is only holding 10inHg. Looks like I can replace with an Evo X for ~$170.

My BOV has 90 degree offset ports, the Evos are inline. Space is pretty tight in that area, have people had good luck plumbing up the inline type? I suspect I'll have to get a new length of 1" hose cut to a custom length based on where it all lays into place.
 

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3SNY - HondaTurtleFTW
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You can get just an injector seal set off of ninjaperformance.com. maybe other vendors as well. cheaper than changing injectors if they are functioning properly.

Sent from my SM-G955U using Tapatalk
 

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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #47 ·
You can get just an injector seal set off of ninjaperformance.com. maybe other vendors as well. cheaper than changing injectors if they are functioning properly.

Sent from my SM-G955U using Tapatalk
True, but with 212K on the original injectors, would you risk going through the job twice? I don't know how big of a pain it is.
 

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True, but with 212K on the original injectors, would you risk going through the job twice? I don't know how big of a pain it is.
Similar to doing plugs:
Stealth 316 - Fuel Injector Installation

Also, why not just have them completely serviced/flowtested/rebuilt? I saw a thread on here for a member doing all of that for under $100. I was actually thinking about messaging him because i am considering doing that for mine. I may also grab a stock set of 360s, have them fully serviced, and throw them in to see if I can run pump gas without getting knock like i am dealing with now (with 550 and SAFC2 no timing control).

The post hasnt been updated in about a year though:
http://www.3si.org/forum/f4/fuel-injector-flow-balancing-cleaning-enter-here-643481/
 

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Color: Arrest Me Red
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If you have a chrome ecu just upgrade inj. No sense in messing with stock 360s. EVO 560s are a nice upgrade and will support mild turbos. 1000cc Inj are better depending on future mods. There is no sacrifice to idle quality with bigger inj fyi. But it sounds like you just need some seals for the inj imo, so you may go that route until car is running tip top.
 

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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #50 ·
Good advice all around. Aside from the leaks I have no reason to suspect the injectors are bad at this point. I'll start out with the $50 3SX injector tune-up kit to get it all resealed (along with a new intake manifold gasket).

I ordered those and an Evo X BOV. Hopefully that'll be the last of the boost leaks.

I have a new PTU and coil set on the bench waiting to be installed as well -the thing misses really bad when trying to accelerate in 5th or 6th on the highway. I've confirmed a lot of leakage where the wires meet the coil pack by misting water over them. It's quite a lightning show once it all gets good and hot. The wires are new, but the coils are original, so hopefully there will be some benefit there after they're replaced.
 

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So i just checked the circuit on the ecu. If there is no signal to the pin the ecu will read -68.2 degrees. If you ground the pin the ecu will read 168 degrees. Also fyi the highest the iat can read is 168 apparently.
 

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Discussion Starter · #52 ·
So i just checked the circuit on the ecu. If there is no signal to the pin the ecu will read -68.2 degrees. If you ground the pin the ecu will read 164 degrees. Also fyi the highest the iat can read is 168 apparently.
Thanks Jester. Once I have it buttoned up I'll take it out for another run and see what kind of values the IAT is reporting. My last log was after installing new coils, a new PTU, and fixing a bunch of vacuum line leaks. The IAT for that short run was back to reading correct (at least, the numbers were reasonable for the ambient conditions), but I have noticed it to be an intermittent issue, so it may just have been a fluke. The car still ran really bad as far as the part-throttle response below ~3000 RPM, also it smells horribly of fuel when idling.

I have to get the new Evo X BOV installed, which is hopefully my biggest leak. I got it all into place and immediately realized that I was having clearance issues between it and the shifter counterweight, which was preventing me from shifting into 1, 3, or 5.



Looking around the forums I can see that I’m not the first person this has happened to. I need to make a trip to the parts store to get an elbow so I can relocate it out of the way, or perhaps print one. I should have some time to work on it this afternoon to see how it runs without that leak.
I’m hoping to relocate it in this position:


Speaking of the printer, I was able to model and print an adapter and save a bunch of money on a filter kit. I was finding K&N 3000GT kits for anywhere between $150 and $200, but they’re essentially just the filter and an attachment adapter for the MAF. I was able to get the K&N RF-1001 filter for $40 and make my own adapter to attach it. I need to tweak the model and print it again as I had a good deal of warping off of the print surface where the bolt holes are, but not bad enough that it wasn’t able to tighten into place. I’ll see how it holds up once I get the car back on the road.
On the print table, you can see how the pucks in the corners didn’t work to hold them down into place:


There was still enough length on the bolts to bring it together:


I used a loft to make a smooth transition between the filter’s oval and the MAF’s octagon.
 

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3SNY - HondaTurtleFTW
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Have you logged what your TOS is reading at part throttle? It may have a dead spot, or dirty spot, where you're having issues.

Sent from my SM-G955U using Tapatalk
 

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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #54 ·
I zip tied the BOV out of the way so I could log a run. I'll relocate it permanently this weekend.

Have you logged what your TOS is reading at part throttle? It may have a dead spot, or dirty spot, where you're having issues.

Sent from my SM-G955U using Tapatalk
Logged TPS? Yes.
Here's the latest run. I pulled out a bunch of parameters and it looks like I'm sampling about 3-5Hz.
https://drive.google.com/open?id=1KnUiv_eLxckw20nak_YQMohZA6xiUTy0

Seems better than it was. Feels like it's misfiring anytime there's a high load, like trying to dig deep in a high gear from 2-3000RPM range. Plus my tach is bouncing now too. Perhaps my $25 Amazon PTU is garbage??

IAT looks good. Knock sum looks good, although there are a few knock count-related parameters to choose from. Those of you who have Chrome ECUs, is Knock Sum the proper one to watch? Or should I be watching/logging Knock Base or Voltage?

I'll try swapping that out and doing another run. I'll also take a look at the front plugs to check their gap and condition.
 

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3SNY - HondaTurtleFTW
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can't check log now(still at work) but I'll look later. should be a smooth percentage change as you increase throttle.

aftermarket ptus are usually junk, or so I've heard. I've always used oem.


I'll look again when I get home, but did you change your fuel filter? sounds almost like low fuel flow.

Sent from my SM-G955U using Tapatalk
 

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1G Foglights b!tches
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Great intro and history. Condolences for your loss but what a great remembrance. Loved the old pics with your father and one with your wife driving also. Very cool. Bet your relationship had its annoyances, just like 3S ownership:D

Unfortunately, I don't have much to offer on all of your nagging sensor and electrical issues. I personally enjoy AEM EMS v2 for these cars and run them in speed density. Easier for me to trouble shoot as it's pretty easy to see when a sensor isn't acting right. Flex fuel is a nice addition also even for a basically stock car. Something to consider.

Good luck and keep us updated!

edit: what printer are you using? any recommendations for a 3d printing beginner for an auto hobbyist?
 

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Thanks Jester. Once I have it buttoned up I'll take it out for another run and see what kind of values the IAT is reporting. My last log was after installing new coils, a new PTU, and fixing a bunch of vacuum line leaks. The IAT for that short run was back to reading correct (at least, the numbers were reasonable for the ambient conditions), but I have noticed it to be an intermittent issue, so it may just have been a fluke. The car still ran really bad as far as the part-throttle response below ~3000 RPM, also it smells horribly of fuel when idling.

I have to get the new Evo X BOV installed, which is hopefully my biggest leak. I got it all into place and immediately realized that I was having clearance issues between it and the shifter counterweight, which was preventing me from shifting into 1, 3, or 5.



Looking around the forums I can see that I’m not the first person this has happened to. I need to make a trip to the parts store to get an elbow so I can relocate it out of the way, or perhaps print one. I should have some time to work on it this afternoon to see how it runs without that leak.
I’m hoping to relocate it in this position:


Speaking of the printer, I was able to model and print an adapter and save a bunch of money on a filter kit. I was finding K&N 3000GT kits for anywhere between $150 and $200, but they’re essentially just the filter and an attachment adapter for the MAF. I was able to get the K&N RF-1001 filter for $40 and make my own adapter to attach it. I need to tweak the model and print it again as I had a good deal of warping off of the print surface where the bolt holes are, but not bad enough that it wasn’t able to tighten into place. I’ll see how it holds up once I get the car back on the road.
On the print table, you can see how the pucks in the corners didn’t work to hold them down into place:


There was still enough length on the bolts to bring it together:


I used a loft to make a smooth transition between the filter’s oval and the MAF’s octagon.
I designed the same thing. I just made it where you could put 4 m6x1.0 screws in from the maf side and thread into the housing. It makes for a simpler design.
 

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1995 Mitsubishi 3000GT VR-4
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Discussion Starter · #59 ·
Great intro and history. Condolences for your loss but what a great remembrance. Loved the old pics with your father and one with your wife driving also. Very cool. Bet your relationship had its annoyances, just like 3S ownership:D
Thanks, and do you mean my relationship with my Dad? Or with the wife? Dad and I were cool; we buried the accident hatchet a long time ago. But so far, the wife isn't the biggest fan of the car :) But I think that'll turn around once I get these kinks worked out.

Unfortunately, I don't have much to offer on all of your nagging sensor and electrical issues. I personally enjoy AEM EMS v2 for these cars and run them in speed density. Easier for me to trouble shoot as it's pretty easy to see when a sensor isn't acting right. Flex fuel is a nice addition also even for a basically stock car. Something to consider.

Good luck and keep us updated!

edit: what printer are you using? any recommendations for a 3d printing beginner for an auto hobbyist?
The printer I use is a Prusa Research i3 Mk2S, and yes I'd recommend it to any beginner. When setup correctly it's able to print on par or better than printers that are 2-3X the cost. When I bought it about a year ago it was $700 for an unassembled kit. It's the only 3D printer I've ever owned, and so far it's been great.

For solid modeling I use Autodesk Fusion 360, which is just awesome. I used to be a SolidWorks user, but they don't offer a reasonable software price for the home gamer, so you either use an illegitimate copy, or you look for something else. Fusion 360 is incredibly capable and for the home user, it's completely free! Essentially, their user agreement is: if you use their software for personal means that net you less than $100,000 per year, then you don't need to pay for a professional license. So you can download and use it for free and get practice with it while you research the printer purchase.

3D printing is a fairly time-consuming hobby to get into as there's still a lot involved in getting a decent print even once you've got your part fully modeled. It's been an awesome hobby that I've enjoyed a lot, but my personal progress has gotten very stagnant in the past few months with baby #1 on the way and the 3000GT issues that I've been trying to give time to.
 

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Premium Member
1995 Mitsubishi 3000GT VR-4
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141 Posts
Discussion Starter · #60 ·
I designed the same thing. I just made it where you could put 4 m6x1.0 screws in from the maf side and thread into the housing. It makes for a simpler design.
That looks good. The printer has been an awesome tool to have. The next part I plan on making is the front bank injector wire holder. That'll be a little harder model than the MAF air filter adapter for sure.
 
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